DE102005057575A1 - Hot film air mass flow meter for use in e.g. diesel engine, of motor vehicle, has field production device, which is designed so that partially homogenous electric field is produced by air mass flow - Google Patents

Hot film air mass flow meter for use in e.g. diesel engine, of motor vehicle, has field production device, which is designed so that partially homogenous electric field is produced by air mass flow

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Publication number
DE102005057575A1
DE102005057575A1 DE200510057575 DE102005057575A DE102005057575A1 DE 102005057575 A1 DE102005057575 A1 DE 102005057575A1 DE 200510057575 DE200510057575 DE 200510057575 DE 102005057575 A DE102005057575 A DE 102005057575A DE 102005057575 A1 DE102005057575 A1 DE 102005057575A1
Authority
DE
Germany
Prior art keywords
air mass
mass flow
electric field
film air
internal combustion
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
DE200510057575
Other languages
German (de)
Inventor
Christoph Gmelin
Axel-Werner Haag
Klaus Habr
Hans Hecht
Bernhard Opitz
Erhard Renninger
Klaus Reymann
Ulrich Wagner
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Robert Bosch GmbH
Original Assignee
Robert Bosch GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Priority to DE200510057575 priority Critical patent/DE102005057575A1/en
Publication of DE102005057575A1 publication Critical patent/DE102005057575A1/en
Pending legal-status Critical Current

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Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through the meter in a continuous flow
    • G01F1/68Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through the meter in a continuous flow by using thermal effects
    • G01F1/684Structural arrangements; Mounting of elements, e.g. in relation to fluid flow
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through the meter in a continuous flow
    • G01F1/68Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through the meter in a continuous flow by using thermal effects
    • G01F1/684Structural arrangements; Mounting of elements, e.g. in relation to fluid flow
    • G01F1/6842Structural arrangements; Mounting of elements, e.g. in relation to fluid flow with means for influencing the fluid flow
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F15/00Details of, or accessories for, apparatus of the preceding groups insofar as such details or appliances are not adapted to particular types of such apparatus
    • G01F15/12Cleaning arrangements; Filters

Abstract

The meter has a field production device (118), which is designed so that a partially homogenous electric field (150) is produced by the air mass flow. The device has a condenser such as plate condenser (116), where electrodes (144, 146) of the condensers are approximately coextensive. The air mass flow flows in a mainstream direction, where the electrical field penetrates the air mass flow perpendicular to the mainstream direction. An independent claim is also included for a method for measuring air mass flow e.g. engine air intake, of an internal combustion engine.

Description

  • The The invention relates to a hot film air mass meter for measuring an air mass flow flowing with a main flow direction. Such hot film air mass meter be especially in the intake of an internal combustion engine used. Furthermore, the invention relates to a method for measurement an air mass flow.
  • was standing of the technique
  • at many processes, for example in the field of process engineering, Chemistry or mechanical engineering, must define a gas mass, in particular an air mass fed become. Which includes in particular combustion processes, which under controlled conditions expire. An important example is the combustion of fuel in internal combustion engines of motor vehicles, in particular with following catalytic emission control. For measuring the air mass flow rate Different types of sensors are used.
  • One type of sensor known from the prior art is the so-called hot film air mass meter (HFM), which is used, for example, in US Pat DE 196 01 791 A1 in one embodiment. Such a hot-film air mass meter usually uses a sensor chip which has a thin sensor membrane, for example a silicon sensor chip. On the sensor membrane is typically arranged at least one heating resistor, which is surrounded by two or more temperature measuring resistors (temperature sensors). In an air flow, which is performed via the Memb ran, the temperature distribution changes, which in turn can be detected by the temperature measuring resistors and can be evaluated by means of a drive and evaluation circuit. Thus, for example, from a difference in resistance of the temperature measuring resistors, an air mass flow can be determined. Various other variants of this type of sensor are known in the art.
  • An example from DE 101 11 840 C2 The known problem with this type of sensor is that contamination of the sensor type can frequently occur, for example contamination by oil, other liquids or other types of contaminants. The sensor chip is usually used directly in the intake tract of the internal combustion engine or in a bypass to the intake tract of the internal combustion engine. In this case, oil may be deposited on the sensor chip and in particular on the sensor membrane during operation of the internal combustion engine. This oil precipitate can lead to an undesired influence of the measurement signal of the sensor chip, in particular since an oil film acts on the surface of the sensor chip on the thermal conductivity of the surface, which leads to the falsification of the measurement signals.
  • The oil contamination can continue also during or shortly after switching off the internal combustion engine, For example, a diesel engine occur. This is special then the case, if after switching off the internal combustion engine one in a crankcase existing overpressure over one Crankcase ventilation in the intake of the internal combustion engine (and thus, for example also in the bypass channel of the hot film air mass meter) degrades. In this case, oil vapor or oil mist is often carried. This oil mist beats at least partially on the sensor chip as a contamination film down and thus causes in particular when turning on the internal combustion engine again a significant measurement signal interference.
  • The DE 101 11 840 C2 proposes a method of preventing soiling on a sensor chip using an auxiliary heater. The sensor chip has a sensor area and an additional heater arranged outside the sensor area. This additional heater is electrically heated so that in the area of the additional heater thermal gradient vortices occur, which lead to precipitation of the contaminants of the flowing medium in the region of the additional heater away from the region of the sensor area.
  • The in the DE 101 11 840 C2 However, the arrangement disclosed and the method disclosed are only of limited suitability for solving the problem of contamination which, as described, is based on several effects. In particular, there is the problem that the oil precipitates now predominantly occur away from the sensor area, but still on the sensor chip itself. If large amounts of contamination accumulate, they can be driven onto the sensor area, for example by air turbulence. Furthermore solves the in the DE 101 11 840 C2 described arrangement also not the above problem that contaminations form especially after switching off the internal combustion engine.
  • advantages the invention
  • Therefore, a hot-film air mass meter is proposed for measuring an air mass flow, in particular in the intake tract of an internal combustion engine, which avoids the disadvantages of the devices known from the prior art. The hot film air mass meter is universally applicable, but is particularly optimized for Mes solution of an air mass flow with a flow velocity between 0 and 60 m / s. Furthermore, a method for operating a hot-film air mass meter according to the invention is proposed.
  • The hot-film air mass meter may, in principle, include all techniques and variants of hot-film air-mass meters known to the person skilled in the art. For example, the Heißfileinuftmassenmesser a sensor chip, for example, a sensor chip with a sensor membrane, include, as in DE 196 01 791 A1 is described. However, other embodiments of hot film air mass meters are possible. The hot-film air mass meter has a sensor surface which can be overflowed by the air mass flow. For example, as described above, this may be the surface of a sensor membrane.
  • One The basic idea of the present invention is oil deposits and other contaminations on the sensor surface to avoid by using electrical effects. For this purpose the hot film air mass meter a field generating device which is configured to create a homogeneous electric field through the air mass flow, which is preferably at least partially homogeneous.
  • This electric field can affect the oil contamination in different ways sensor surface to take. It should be noted that the air mass flow usually an oil mist Contains (aerosol) with the smallest oil droplets, which be carried along with the air mass flow. This effect can be both during operation of the internal combustion engine as well as, as described above, occur after switching off the internal combustion engine. These are oil droplets in many cases electrically charged. This electrical charging takes place, for example by molecular friction, wall joints with, for example the wall of a flow channel, by ambient radiation or by interaction with other oil droplets. additionally can charge the oil droplets through an electric field is amplified be accelerated since in this case already charged oil droplets, with other droplets collide and thus generate new charges in a kind of "avalanche effect".
  • The such charged oil particles are deflected in the electric field according to their polarity. That way you can the oil droplets by electrical Distraction away from the sensor surface become.
  • One Another effect may be that oil droplets in the electric field polarized without a net charge. To this Way, from the oil droplets each an electric dipole. Since in each case the positively charged part of a first oil droplet and the negative part of a second oil droplet attract each other, can two such polarized oil droplets easily merge together (coagulate). That's how you form yourself from the smallest oil droplets, which are carried by the air mass flow, large, heavy drops, which then fail due to the gravity acting on them. Also in this way can the oil mist from the sensor surface be kept away, especially if the sensor surface during operation of the hot film air mass meter is arranged vertically.
  • The Field generating device may include one or more capacitors In particular, a plate capacitor, but wherein the plates of the plate capacitor need not necessarily be parallel. there it is preferred if the electrodes of the at least one capacitor at least approximately coextensive. It can Deviations of 50%, preferably not more than 10% and especially preferably not more than 5%, preferably one generate at least partially homogeneous electric field. has the hot film air mass meter a flow channel, in particular a bypass channel, on, so can the electrodes of the capacitor in the flow channel be introduced. These can be separate electrodes, for example in the form of introduced into the flow channel metal layers. Alternatively you can also the walls of the flow channel itself with a metallization, or the flow channel itself may be a metallic component, in particular one at least partially metallic lid and / or bottom part, have. Also, several can Capacitors are arranged in series, such as a capacitor in front of the sensor chip, a capacitor after the sensor chip.
  • In many cases, the air mass flow will flow in a main flow direction. If a flow channel is used, for example a bypass channel, then the term "main flow direction" is to be understood locally in each case, whereby the term "main flow direction" is to be understood in each case as the main transport direction of the air mass flow at the respective location in the flow channel. Local turbulences should be neglected. It is particularly preferred if the electric field penetrates the air mass flow substantially perpendicular to the main flow direction. In this way, the deflection effect described above is particularly well utilized. Preferably, the electric field in the installed state of the Heißfileinuftmassenmessers, beispielswei se in the intake of the internal combustion engine with horizontally stationary internal combustion engine, even horizontally. In this way precipitation of coagulated droplets can be enhanced.
  • Around the above-described effects of distraction and precipitation (besides which can still have other electrical effects act) is to support it is preferred if the air mass flow before reaching the sensor surface a Drift distance of at least 1 mm, in particular at least 3 mm and particularly preferably travels at least 5 mm in the electric field. This can be done, for example, by appropriate dimensioning of the be carried out capacitor described. In particular, for example, if a flow channel (For example, a bypass channel) is used, the entire route the bypass channel are provided with a capacitor, for example by metallizing each cover and bottom of the bypass channel. It is particularly preferred if this is preferably at least partially homogeneous electric field at least in a partial area a field strength in one Range from 1 kV / m to 5 MV / m, in particular 10 kV / m to 2.5 MV / m and more preferably at approximately 0.4 MV / m. These field strengths have proven in field tests to be particularly effective and yet technical well realized and manageable proven.
  • As described above, the contamination effect occurs in particular Turning off the internal combustion engine, when offset with oil mist Air in the crankcase relaxed and diffused through a crankcase ventilation opening in the intake. Accordingly, the hot film air mass meter according to the invention can also be different operate. On the one hand, the field-generating device can be used throughout Operation or just during Partial phases of the operation of the internal combustion engine an electric Create field and in this way taking advantage of the described Effects continuously prevent contamination of the sensor surface. Furthermore, however, it is alternatively or additionally also preferred that Field generating device after switching off the internal combustion engine use. Accordingly, a method is proposed in which the field generating device after switching off the internal combustion engine for one predetermined overrun period generates an electric field. Basically Any overtravel period can be used. Especially have follow-up periods between 3 sec and 10 min, preferably between 5 sec and 5 min and more preferably between 10 sec and proven for 3 minutes. In this way, caused by diffusion of oil mist contamination the sensor surface avoided at standstill of the internal combustion engine or strong be reduced. It should be noted that the above used term of "main flow direction" in case of standstill the internal combustion engine is wide, since in this case scenarios may occur, in which oil mist "from both Directions "to sensor surface stream. Therefore For example, the drift path described above may be arranged "before" and / or "after" the sensor surface Thus, with reference to the main flow direction in the operation of Internal combustion engine upstream or downstream of the sensor surface. It can also different electric fields may be provided, for example an electric field "downstream" of the sensor surface, which only switched on after switching off the internal combustion engine is going to be a back diffusion of oil mist against the main flow direction during operation of the internal combustion engine after switching off the internal combustion engine to prevent or the effects of contamination by this back-diffusion to diminish.
  • in the Contrary to the devices known from the prior art to reduce or avoid oil contamination on the sensor surface the hot film air mass meter according to the invention and the described method of operating the same by numerous advantages out. One advantage, for example, is that oil deposits overall on the sensor surface be avoided by oil before reaching the sensor surface precipitated and / or from the sensor surface is kept away. There are thus no accumulations of oil in the Near the sensor surface, which subsequently could be carried by air turbulence on the sensor surface. The System is characterized by an increased robustness and susceptibility to interference out.
  • Furthermore, the hot-film air mass meter described is comparatively simple. There are no additional control mechanisms required, for example, to maintain certain temperature ranges on the sensor surface, as for example in the DE 101 11 840 C1 the case is. Furthermore, no microsystem changes in the sensor surface itself are required, for example, additional microstructures on a sensor chip. Already existing sensor chips can thus be further used by simply supplementing them with a field generating device. A change in the lithographic processes or the layout of sensor chips is usually not required.
  • The field generation device can be realized by simply introducing electrodes into a flow channel. As described above, For example, metal foils can be used, or even walls of a flow channel can be metallized. For this purpose, known to those skilled, cost-effective and reliable large-scale production, for example, injection molding process for the preparation of a flow channel, followed by standard metallization. For example, there are numerous techniques for subsequently metallizing injection-molded components, in particular with the aid of metallizable plastics and / or a subsequent Metallisierbarmachung the plastics by applying, for example, metal nuclei and subsequent metallization, for example in a chemical Metallisierungsbad. Such techniques are known to those skilled in the art. It is also possible to apply structured metallizations to plastics, wherein, for example, the methods known from the art of injection-molded printed circuit boards (molded interconnect devices, MID) (eg hot embossing, laser structuring, etc.) can be used. In this way, the hot-film air mass meter described can be produced by a low-cost and reliable manufacturing method with slight modification of already known hot-film air mass meter types.
  • drawing
  • Based the drawing, the invention is explained in more detail below.
  • It shows:
  • 1 a Heißfileinuftmassenmesser used in an intake of an internal combustion engine;
  • 2 a section through a bypass channel of a Heißfileinuftmassenmessers with a protruding into the bypass channel chip carrier;
  • 3 a section through the bypass duct of an embodiment of a Heißfileinuftmassenmessers with cutting plane perpendicular to the cutting plane according to 2 ; and
  • 4 a cover part of a Heißfileinuftmassenmessers for placement on the bypass channel according to 2 ,
  • embodiments
  • In 1 is an example of a hot film air mass meter 110 shown, which in the intake 112 an internal combustion engine is used. Such hot film air mass meter 110 are commercially available and prior art. The hot film air mass meter 110 is designed to detect the flow direction of an exhaust flow in pulsating flow and is designed for load sensing in internal combustion engines with gasoline or diesel fuel injection. The installation of the hot film air mass meter 110 usually takes place between an air filter and a throttle device and is usually carried out as a preassembled module in the form of a plug-in sensor, which is a measuring housing 114 having.
  • In the 2 to 4 is an embodiment of a Heißfileinuftuftmessers invention 110 shown in which a plate capacitor 116 as a field generating device 118 is used. It shows 2 the hot film air mass meter 110 with opened measuring housing 114 , wherein the bypass channel 120 is visible. The measuring housing 114 thus includes an electronics area 122 in which the (in 2 not shown) control and evaluation of Heißfileinuftmassenmessers 110 is housed, as well as a flow area 124 in which the bypass channel 120 is included. As in 1 represented, projects the flow area 124 in the intake tract 112 the internal combustion engine. From the electronics area 122 protrudes from a chip carrier 126 with a sensor chip inserted therein 128 in the bypass channel 120 , The chip carrier 126 For example, a metallic chip carrier 126 be, for example in the form of a sheet metal part. In another embodiment, the chip carrier 126 also be a plastic part, for example one to an electronics area 122 received printed circuit board molded sensor nose, which in the bypass channel 120 protrudes. In a depression of the chip carrier 126 is the sensor chip 128 let in, leaving its sensor surface 130 from the bypass channel 120 passing air mass flow is overflowed.
  • With reference number 132 are in 2 Diffusion paths of the oil mist drawn in the air mass flow. These diffusion paths 132 are the paths that the oil mist from the intake tract 112 towards the sensor chip 128 cover when the internal combustion engine is switched off. During operation of the internal combustion engine, however, the air mass flow flows in the region of the sensor chip 128 with a main flow direction through the bypass channel 120 , wherein the main flow direction in 2 symbolic with the arrow 134 is designated. To overflow the sensor surface 130 to ensure is the chip carrier 126 upstream with a leading edge 136 fitted.
  • The measuring housing 114 is in the perspective view according to 2 viewed from above in the open state. In 4 is a lid part 138 shown in perspective, which after flaps about a vertical axis on the measuring housing 114 in 2 Can be placed on the bypass channel 120 close. The D ckelteil 138 then forms an integral part of the measuring housing 114 , Clearly in the cover part, the boundary structures 140 of the bypass channel 120 to recognize. Furthermore, it can be seen that the walls of the bypass channel 120 not run parallel in all areas, but that a flow guide by local narrowing or widening of the bypass channel 120 can be done. For example, in the area of the bypass channel 120 in which the chip carrier 126 protrudes, a convergence ramp 142 formed, so that is narrowed in this area, the flow cross-section.
  • In 3 is a section through the area of the bypass channel 120 in the area of the convergence ramp 142 shown. The cutting line runs in 2 horizontally through the chip carrier 126 , and the line of sight is in 2 from below, parallel to the drawing plane. In this illustration, the embodiment of the field generating device 118 especially clear. It can be seen that this field generating device 118 is composed in this embodiment by a first electrode 144 on the lid part 138 and a second electrode 146 on a floor part 148 of the measuring housing 114 , Be the two electrodes 144 . 146 charged differently, an electric field is formed between them 150 out, which in 3 is shown symbolically. The electric field is substantially homogeneous in this embodiment and deviates from the homogeneity only in the edge regions. For typical channel widths between 2 and 10 mm, voltages up to approximately 5 kV were used in tests. When using non-metallic chip carriers 126 For example, in the form of injection molded components, the field lines in the area of the chip carrier 126 only insignificantly influenced. However, other embodiments are possible, in particular embodiments with metallic chip carriers 126 ,
  • The two electrodes 144 . 146 are in this embodiment by simply applying Leitlack on the channel walls of the bypass channel 120 generated. This is by looking at the 2 and 4 recognizable. In 2 is the second electrode 146 , which on the bottom part 148 of the measuring housing 114 is applied, visible. In the perspective view according to 2 is this second electrode 146 partly through the chip carrier 126 covered. In 4 is the first electrode 144 , which on the cover part 138 is applied, recognizable. By unfolding the lid part 138 on the measuring housing 114 form the first electrode 144 and the second electrode 146 in the 3 illustrated capacitor structure.
  • How out 3 As can be seen, the electric field begins 150 not directly at the leading edge 136 of the chip carrier 126 but the electrodes 144 . 146 are designed such that the air mass flow already a drift path 152 through the electric field 150 has traveled before this the sensor surface 130 reached. In this way it is ensured that the above-described effects of the precipitation of coagulated oil droplets or the deflection of charged oil droplets can act sufficiently before the air mass flow reaches the sensor surface 130 reached. The precipitation of oil droplets takes place in this illustration according to 3 , which shows the viewing direction from below, vertically out of the plane of the drawing. The electric field 150 is approximately horizontal in this case, but also deviations from the horizontal (preferably by not more than 20 °) can be tolerated.
  • Furthermore, in 3 to realize that the electric field 150 also not immediately after the sensor surface 130 ends, but only to a Nachdriftstrecke 154 behind the sensor surface 130 , For example, this Nachdriftstrecke 154 be approximately as long as the drift distance 152 , Through this Nachdriftstrecke 154 ensures that even after switching off the internal combustion engine against the main flow direction 134 flowing oil vapors (see the diffusion paths 132 in 2 ), what a 3 flow from the right, the sensor chip can not or only slightly contaminate. In the embodiment according to the 2 to 4 is the drift distance 152 chosen longer than the Nachdriftstrecke 154 , Typical lengths of drift paths 152 . 154 lie in the range of one to fifty millimeters.
  • That in the 2 to 4 described embodiment of the Heißfileinuftmassenmessers invention 110 represents only one of several ways to Reali tion of the inventive principle. The electrodes 144 . 146 can easily, for example, through the measuring housing 114 applied conductor tracks, electrically contacted and connected to a corresponding voltage source. Alternatively, a complete metallization of the walls of the bypass channel 120 possible, so in this case the drift path 152 or the Nachdriftstrecke 154 the entire bypass channel 120 includes. Furthermore, separate, from the cover part 138 and bottom part 148 separate electrodes in the bypass channel 140 be introduced, so that, for example, the electric field 150 not over the entire width of the bypass channel 120 extends. In this way you can work with lower voltages. Furthermore, it is also conceivable to use other electrode geometries, for example other geometric shapes of the electrodes 144 . 146 , Also, the chip carrier 126 , which, as described above, can also be metallic, even be used as an electrode.
  • As described above, it is particularly preferred if the hot-film air mass meter according to the invention 110 after switching off the internal combustion engine is still operated for a certain follow-up duration. In this way it prevents over the diffusion ways 132 to the sensor chip 128 reaching oil mist can contaminate this at standstill of the internal combustion engine. This ensures in particular that even after renewed switching on the internal combustion engine of Heißfiluuftmassenmesser 110 almost immediately available again for corresponding measurements and thus for motor control.

Claims (9)

  1. Hot film air mass meter ( 110 ) for measuring an air mass flow, in particular in the intake tract ( 112 ) of an internal combustion engine, wherein the hot film air mass meter ( 110 ) a sensor surface which can be overflowed by the air mass flow ( 130 ), characterized by a field generating device ( 118 ) which is designed to generate a preferably at least partially homogeneous electric field ( 150 ) by the air mass flow.
  2. Hot film air mass meter ( 110 ) according to the preceding claim, characterized in that the field generating device ( 118 ) has a capacitor, in particular a plate capacitor ( 116 ), the electrodes ( 144 . 146 ) of the capacitor are at least approximately coextensive.
  3. Hot film air mass meter ( 110 ) according to the preceding claim, characterized by at least one flow channel, in particular a bypass channel ( 120 ), the electrodes ( 144 . 146 ) an introduced into the flow channel metal layer and / or applied to walls of the flow channel metallization and / or a metallic component of the flow channel, in particular a metallic component of a cover part ( 138 ) and / or a bottom part ( 148 ) of the flow channel.
  4. Hot film air mass meter ( 110 ) according to one of the preceding claims, characterized in that the air mass flow with a main flow direction ( 134 ), the electric field ( 150 ) the air mass flow substantially perpendicular to the main flow direction ( 134 ) penetrates.
  5. Hot film air mass meter ( 110 ) according to one of the preceding claims, characterized in that the electric field ( 150 ) in the installed state of the hot-film air mass meter ( 110 ) is substantially horizontal.
  6. Hot film air mass meter ( 110 ) according to one of the preceding claims, characterized in that the electric field ( 150 ) is configured such that the air mass flow before reaching the sensor surface ( 130 ) a drift path ( 152 ) of at least 1 mm, in particular of at least 3 mm and more preferably of at least 5 mm in the electric field ( 150 ) covers.
  7. Hot film air mass meter ( 110 ) according to one of the preceding claims, characterized in that the preferably at least partially homogeneous electric field ( 150 ) has a field strength in a range from 1 kV / m to 5 MV / m, in particular 10 kV / m to 2.5 MV / m, and particularly preferably at approximately 0.4 MV / m, at least in a partial region.
  8. Method for measuring an air mass flow of an internal combustion engine, in particular in the intake tract of the internal combustion engine, using a hot-film air mass meter ( 110 ) according to one of the preceding claims, characterized in that the field generating device ( 118 ) after switching off the internal combustion engine for a predetermined follow-up period an electric field ( 150 ) generated.
  9. Method according to the preceding Claim, characterized in that the follow-up period between 3 sec and 10 min, especially between 5 sec and 5 min and especially preferably between 10 seconds and 3 minutes.
DE200510057575 2005-12-02 2005-12-02 Hot film air mass flow meter for use in e.g. diesel engine, of motor vehicle, has field production device, which is designed so that partially homogenous electric field is produced by air mass flow Pending DE102005057575A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE200510057575 DE102005057575A1 (en) 2005-12-02 2005-12-02 Hot film air mass flow meter for use in e.g. diesel engine, of motor vehicle, has field production device, which is designed so that partially homogenous electric field is produced by air mass flow

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE200510057575 DE102005057575A1 (en) 2005-12-02 2005-12-02 Hot film air mass flow meter for use in e.g. diesel engine, of motor vehicle, has field production device, which is designed so that partially homogenous electric field is produced by air mass flow

Publications (1)

Publication Number Publication Date
DE102005057575A1 true DE102005057575A1 (en) 2007-06-06

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010031647A1 (en) * 2008-09-17 2010-03-25 Robert Bosch Gmbh Sensor arrangement for determining a parameter of a fluid medium
WO2011147681A1 (en) * 2010-05-28 2011-12-01 Continental Automotive Gmbh Air mass flow meter
DE102013212162A1 (en) 2013-06-26 2014-12-31 Robert Bosch Gmbh Sensor device for detecting at least one property of a fluid flowing in a channel
WO2016165868A1 (en) 2015-04-15 2016-10-20 Robert Bosch Gmbh Sensor for determining at least one parameter of a fluid medium flowing through a measurement channel

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010031647A1 (en) * 2008-09-17 2010-03-25 Robert Bosch Gmbh Sensor arrangement for determining a parameter of a fluid medium
WO2011147681A1 (en) * 2010-05-28 2011-12-01 Continental Automotive Gmbh Air mass flow meter
DE102010020264A1 (en) * 2010-05-28 2011-12-01 Continental Automotive Gmbh Air flow sensor
CN102918366A (en) * 2010-05-28 2013-02-06 大陆汽车有限责任公司 Air mass flow meter
CN102918366B (en) * 2010-05-28 2016-05-25 大陆汽车有限责任公司 Air flow meter
US9658092B2 (en) 2010-05-28 2017-05-23 Continental Automotive Gmbh Air mass flow meter
DE102013212162A1 (en) 2013-06-26 2014-12-31 Robert Bosch Gmbh Sensor device for detecting at least one property of a fluid flowing in a channel
US10006793B2 (en) 2013-06-26 2018-06-26 Robert Bosch Gmbh Sensor device for detecting at least one property of a fluid medium flowing in a channel
WO2016165868A1 (en) 2015-04-15 2016-10-20 Robert Bosch Gmbh Sensor for determining at least one parameter of a fluid medium flowing through a measurement channel
DE102015206708A1 (en) 2015-04-15 2016-10-20 Robert Bosch Gmbh Sensor for determining at least one parameter of a fluid flowing through a measuring channel

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